Absorbent articles such as diapers, training pants, incontinence products, feminine hygiene products, swim undergarments, and the like typically include a liquid-permeable body side liner, a liquid-impermeable outer cover, and an absorbent core. The absorbent core is typically located in between the outer cover and liner for taking in and retaining liquids (e.g., urine) exuded by the wearer. Various types of moisture or wetness indicators have been suggested for use in absorbent articles. For instance, conductive threads, foils, and/or other components can be included in one or more layers of the article. The threads, foils, and/or other components can be used to sense a change in an electrical characteristic or property which depends on wetness (or other condition(s)) of the garment.
For instance, the presence of urine or other wetness can be determined based on sensing a change in resistance, conductance, impedance, capacitance, and/or any other parameter or parameters. The device or devices used to sense the change in property or properties can produce a visual, audible, or other signal indicating a change in the condition of the absorbent article.
As an example, a pair of spaced apart parallel conductors may be situated within the absorbent material of an undergarment, with the conductors positioned to connect to a monitor included in or removable situated on the undergarment. The conductors may be configured to act as a voltage divider circuit, with the monitor detecting the wet/dry state of the undergarment based on the voltage level at a constant current. For instance, when the undergarment is dry, the circuit may act as an open circuit with practically infinite resistance, while the circuit may have a lower resistance when wet.
Monitoring of the status of an absorbent garment can be desirable to various users in many varied situations. For instance, the caregiver of an infant may be alerted to the condition of a diaper in order to change the diaper in an expeditious manner. A caregiver to a person with bladder or bowel control problems and/or user of an incontinence product may wish to be alerted to the presence of urine or other exudates for similar reasons. As yet another example, a caregiver using disposable absorbent training pants to toilet train a child may wish to know the status of the training pants for the purposes such as changing the pants when needed, tracking progress of toilet training, and providing guidance to the child during the oftentimes-stressful toilet training process.
Existing monitoring systems for absorbent articles are somewhat limited in user interface options. For instance, if included in a monitoring device adapted to be situated on a garment, input devices such as switches, buttons, and/or other input devices add bulk to the monitoring device. If included in or on the article itself, switches, buttons, and/or other input devices add bulk and complexity to the article, which can result in discomfort and/or can complicate the manufacturing process.